ExpressMix, even though there's no demo, they have some really great videos up on their website here. Especially checkout the "10 Sequence Editor Power Tips" video, that'll really give you a good taste of DP in action:
http://www.motu.com/products/software/d ... er_content
In some ways, watching videos is even better then a demo. It'll show you what using DP is like once you get up to speed, and not just fumbling around with a demo for the first time. The videos are VERY well done, and really go in to how to perform various tasks effectively and efficiently.
The strength of DP is in how deep it is, and how well it works when you've used it for a while. Some programs are faster and easier to learn and get up to speed, but once you're there, it's not really all that fast or feature-driven. The problem with demos is that the first month of using a new program (of the magnitude of a DAW) really doesn't give you a good impression of how it will be over the long term. For instance, I learned Pro Tools very quickly, but when compared to DPs tool and feature set, it's nowhere as powerful, and just seems clunky in hindsight. But had I used a timed demo of both, I probably would have gone with PT because I was able to hit the ground running.
That said, MOTU may need to think about making a demo anyway, because Windows users are so used to it. Us Mac users are kinda used to not having demos. Many times, even software that's cross platform will only have a Windows demo, so demoing software doesn't typically enter our minds. It's why Apple doesn't offer demos either. Now that DP is cross platform, they're going to be dealing with some slightly different ideals in software usage, and they may want to think about bending to them slightly.
BTW: MLC, I know you're trying REALLY hard to keep your tongue at bay with this new crowd of Windows users. Just keep in mind that this forum is an absolutely VITAL part of MOTU's success. We're going to start getting an influx of people totally outside our normal software philosophy ideals. You don't necessarily always deal well with that. Maybe you should let other members deal with it. We don't want to scare away potential DP8 users. I don't mean to offend.